7Yuan JM, Wang XL, Xiang YB, et al. Preserved foods in relation to risk of nasopharyngeal carcinoma in Shanghai, China [ J]. Int J Cancer, 2000, 85(3) :358 -363.
8Lin TM, Chang HJ, Chen C J, et al. Risk factors for nasopharyn- geal carcinoma[ J]. Anticancer Res, 1986, 6 (4) :791 - 796.
9Fachiroh J, Sangrajrang S, Johansson M,et al. Tobacco consump-tion and genetic susceptibility to nasopharyngeal carcinoma ( NPC ) in Thailand [ J ]. Cancer Causes Control, 2012, 23 ( 12 ) : 1995 - 2002.
10Lee A, Foo W, Mang O, et al. Changing epidemiology of naso- pharyngeal carcinoma in Hong Kong over a 20-year period ( 1980- 1999): an encouraging reduction in both incidence and mortality [J]. IntJCancer, 2003, 103(5) :680 -685.